One of the key targets in the development of RIAs (Rich Internet Applications) is good performance. You can't provide a good user experience if your feature-rich application has poor performance. The question is how to measure the performance of a JavaFX application? How to find issues before the users of your application encounter them?
The good news is that you can profile JavaFX Applications in NetBeans IDE. The NetBeans Profiler enables developers both to evaluate time spent on methods execution and measure the memory allocated for every object. For more details, see Profiling JavaFX Applications in NetBeans IDE